Valve-to-tappet clearance setting tool



Dec. 2, 1952 J. M. GARRETT EI'AL 2,619,783

' VALVE-TO-TAPPET CLEARANCE SETTING TOOL Filed March 7, 1949 v 12'v 7 2 L- nu '6 Patented Dec. 2, T952 VALVE-TO-TAPPET CLEARANCE SETTING TOOL James M. Garrett, San Antonio, and Wesley E. Tollett, Carrizo Springs, Tex.

Application March 7, 1949, Serial No. 80,084

6 Claims.

This invention relates to a valve-to-tappet clearance setting tool.

An object of the invention is to provide a tool of the character described whereby the amount of clearance between a valve and tappet, after grinding, may be ascertained so as to know how much to grind off of the end of the valve stem to cause proper seating of the valve after the valve and seat are ground, and to have the desired valve-to-tappet clearance.

It is another object of the present invention to provide equipment of the character described which may be readily applied to the motor block in order to obtain the exact information desired and the exact adjustment of the valve stem in the holder preparatory to the grinding operation.

It is a further object of the present invention to adjust readily valve to tappet clearances with predetermined length clearance bars to meet any desired specifications, which bars would eliminate the present customary use of feeler gauges, depth gauges, and micrometers, it being obvious that a considerable saving of time, as well as greater accuracy, will result by the elimination of multiple operations now in usage. Furthermore it may readily be understood that there would be more accuracy achieved because of the lessening of moveable and wearable means now in usage. In this new invention, there is no variable means of wear or possible misreading or misadjustment of instruments possible by using any one predetermined length clearance bar with this new tappetto-valve clearance setting tool.

Other objects and advantages will be apparent from the following specifications which are illustrated by the accompanying drawings, wherein:

Figure 1 is a fragmentary sectional view of a motor showing the setting tool, in section, therein.

Figure 2 is a cross sectional view taken on the line 2-2 of Figure 1.

b Figure 3 is a side elevation of the clearance Figure 4 is a side view, partly in section, of the setting tool in its relation to a grinding machine and Figure 5 is a cross sectional view taken on the line 5-5 of Figure 4.

Referring now more particularly to the drawings, the numeral I designates a tubular housing as a whole. One end of this housing is of a size to snugly fit into the seat 2 of the valve stem guide, when the latter is removed. This guide is indicated by the numeral 3 in Figure 1.

The outer end of the housing is of somewhat greater'diameter than the inner end thereof and 2 between the outer and inner end the housing has an external tapering area indicated by the numeral 4 and also has an inside annular seat 5. The taper of the area 4 is the same as the normal taper of the valve seat, said valve seatbeing indicated by the numeral 6. g

The numeral 1 designates a guide which is formed of two similar, longitudinal, sections having a central longitudinal bearing, designated generally by the numeral 8, of a size and shape to snugly receive the stem 9 of the valve II). This valve and stem are of the conventional kind used in certain types of internal combustion motors.

The guide I is of substantially the same length, transverse diameter and external contour of the conventional valve guide of the motor. This conventional guide is indicated by the numeral I I in Figure 1.

The valve I I] has a tapering face I2 which is adapted to seat on the valve seat 6 to form a close fit therewith. V

The numeral I 3 designates the conventional camshaft of the motor having cams such as I4 thereon opposite the respective valve stems and during the normal operation of the motor the valves thereof will be alternatively lifted by the corresponding cams and seated by the coil pressure springs I5 which are mounted in the motor block on suitable spring seats as I6 on the inner ends of the stems.

The valve seat 6 and the valve face I2 must occasionally be ground to form a close fit to prevent leakage. A certain amount of material will be removed during the grinding process and therefore, in order to allow the valve to seat and to have the proper valve-to-tappet clearance after this grinding process, the valve stem 9 must be reduced in length an amount equal to the total taken off of valve seat 6 and valve face I2 plus the desired valve-to-tappet clearance as a result of the grinding process.

When a valve and its guide I I have been re-'- moved and the seat 6 and face I2 ground the clearance bar I1 is attached to the inner end of the valve stem as shown in Figure 1. One end of this clearance bar has clamp fingers I8, I8 which clamp the enlarged inner end of the valve stem 9 to hold the adjacent end of said valve stem and the clearance bar closely together. The guide I is then applied to the stem 9 and inserted in the housing and the assembly is inserted into the guide seat 2 of the conventional guide II.

The th of bar I! is equal to the distance from where areas 4 and 6 come into contact to where the outer end of housing I comes into With the housing, the guide I, the valve and stem with bar 11 attached, assembled as shown in Figure 1 and inserted into the seat 2 with the inner end of the bar I! against the low side of the corresponding tappet the face ll of the valve will clear the outer end of housing a distance equal to the clearance between the face l2 and seat 6 caused by the grinding process, plus the desired valve-to-tappet clearance.

The guide I is then clamped about the valve stem 9 and clamped immovably to the housing by means of a set screw l9 which is screwed through the housing with its inner end clamped against one section of the guide 1.

The assembly, as so fixed, is thenremoved from the motor and the clearance bar I! removed.

The numeral 20 designates a suitable base on one end of which is fixed a motor 2|, such as an electric motor, and on one end-of the motor shaft there. is a grinding disc 22. In front of this grindingdisc and fixed on thebase 20 there is a suitable clamp 23. in which the small end of the housing .I is inserted with the end of the valve stem against the grinding disc 22, and said clamp is then secured about said housing by means of the'conventionalclamp screw 24. The set screw i9 is then released and the motor started and pressure is applied against the valve [9 in a directlonindicated, by an arrow in Figure 4 so that the opposite end of the stem 9 is forced against the grinding; disc 22' and the stem is ground off until the valve In seats against the corresponding outer end of the housing I.

It isobvious that the amount ground off the end ofqthevalve stem would equal the total amount taken oil of the valve face l2 and the valve seat 6 plus the, desired valve to-tappet clearance, so that when the valve is installed in its operative position as shown at the. right in Figure .1, the valve face [2 willseat closely against its corresponding seat 6, and there will be-the desiredclearance between the end of the valve stem Band the tappet.v

It is understood that the clearance bar I! can be of various predetermined lengths to accommodate various desired clearances betweenlower end of'valve stem and tappet.

The drawings and descriptions are illustrative merely and are not intended to limit the invention the precise,. mechanical construction shown, while the broad principle of the-invention will be defined by the appended claims.

What we claim is:

A. tool of the character described comprising, a tubular housing one end of which .is shaped to; fit into a valve stem guide seat of an internal combustion motor and whose other end is internallygand externally enlarged and formed with an inside seat and an outside tapered area adapted for seating engagement with the corresponding motor valve. seat, and said housing'having avalve-face engaging portion spaced longitudinally of the housing from the tapered area, a. valve stem guide Within said enlarged end adapted to seat on said inside seat andshaped to receive the stem of a valve 'thereth-rough, means for clamping the guide to the valve stem and for also clamping the guide in the housing and a clearance bar of a preselected length greater than the distance between the tapered area and the valve-face-engaging portion of. the housing by an amount at least equal to the desired tappet-to-valve clearance and adapted to '4 be aligned with the valve stem and removably secured in endwise abutting relation to the inner end of the stem.

2. A tool of the character described comprising, a tubular housing one end of which is shaped to fit into a valve stem guide seat of an internal combustion motor and whose other end is enlarged externally and internally forming an inside seat and an outside tapered area adapted for seating engagement with the corresponding motor valve seat, and said housing having a valve-face engaging portion spaced longitudinally of the housing from the tapered area, a stem guide on said inside seat and shaped to receivethe stem of a valve therethrough, means for clamping said guide to the stem and in the housing and a clearance bar of a length greater than the distance between the tapered area and the valve-face-engaging portion of the housing by an amount at least equal to the desired tappetto-valve clearance andwadapted to be removably secured in endwise abutting relatio-nto the inner end of the stem.

3. A tool of the character described comprising, a tubular housing one endvof which is shaped tofit into a valve stem. guide seat of an internal combustion motor and whose other end is enlarged externally forming an external tapered area on the housing which conforms to the taper of the corresponding motor valve seat, said other end being also enlarged internally forming an inside seat and having a valve-face engaging portion spaced longitudinally from the tapered area, a stem guide on said inside seat and shaped to receive the stem of a valve therethrough, means for clamping said guide to the stem and in. the housing and a clearance bar of a length greater than the distance between the tapered areaand the valve-face-engaging portion of the housin by the amount of the desired tappet-tovalve clearance and adapted to be removably secured in endwise abutting relation to the inner end of the stem.

4. A tool of the character described comprising, a tubular housing one end of which'is shaped to fit into a valve stem guide seat of an internal combustion motor and Whose other end is enlarged externally and internally forming an in-' side seat, a stem guide formed of longitudinal sections and seated on said inside seat and shaped to receive the stem of a valve therethrough said housing having an external seat which is shaped to fit against the corresponding valve motor seat, and a valve-face engagingportion. spaced longitudinally of the. housing from the external seat, a set screw threaded through the wall of the housing against the stem guide for clamping said guide to the stem and fixing said guide and stem relative to the housin and a clearance bar of a length greater than the distance between the tapered area and the valveface-engaging portion of the housing by an amount equal to the desired tappet-to-valve clearance and adapted to be removably secured in endwise abutting relation to the inner end of the stem.

5. A tool of the character described comprising, a tubular housing, one end of which is shaped to fit into a. valve stem guide seat of an internal combustion motor and whose other end is enlarged externally forming an external tapering seat which is adapted to fit against the valve seat of the motor, said other end being also internally enlarged forming an inside seat and the housmg also having'a valve-face-engaging Portion spaced longitudinally of the housing from the external seat, a stem guide on said inside seat and formed of longitudinal sections and having an axial bearing therethrough to receive the stem of a valve, means for clamping said guide to the stem therein and in the housing and a clearance bar of a length greater than the distance between the external seat and the valveface-engaging portion of the housing by an amount equal to the desired tappet-to-valve clearance and adapted to be removably secured in endwise abutting relation to the inner end of the stem.

6. A tool of the character described comprising, a. tubular housing one end of which is shaped to fit into a valve stem guide. seat of an internal combustion motor and whose other end is enlarged internally forming an inside seat, the housing having an external seat which is shaped for seating engagement with the valve seat of the motor, and a valve-face-engaging portion spaced longitudinally of the housing from said external seat, a stem guide on said inside seat JAMES M. GARRETT. WESLEY E. TOILETT.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,873,067 Stromgren Aug. 23, 1932 2,104,234 Linne Jan. 4, 1938 2,217,952 Huggins Oct. 15, 1940 2,316,591 Johnson Apr. 13, 1943 

